Jeremy Hobson: Supermarkets around the country are responding to the latest threat to their business: extreme couponing. So far, Rite Aid, Krogers, Publix and Target have joined in the crackdown by limiting the number of coupons people can use.

For more on the coupon craze, let's turn to L.A. Times Consumer Columnist David Lazarus. David, Good morning.

David Lazarus: Good morning.

Hobson: So David, is this for real -- coupons are really being used a lot right now?

Lazarus: Oh yeah. In fact, in 2009 -- that's the latest year for which the people who crunch these kinds of numbers have been looking at the data -- we saw a 29 percent increase in coupon use. What that means is that 3.3 billion coupons being redeemed for merchandise goods equivalent to nearly $1 billion in savings. So that's a whole lot and clearly indicative of people being concerned about the economic downturn.

Hobson: And is this something we see in every economic downturn, or just this one?

Lazarus: No, it looks like this is a regular thing, that when the economy goes sour, people go to coupons. But in this current downturn, coupon use is much slower than we saw in 1992, the last time we really hit a speedbump with the economy, when nearly 8 billion coupons were redeemed. And I've been trying to figure that out -- I'm guessing it's a generational shift, and the current folk out there making up the consuming public just aren't as old school about coupons as others.

Hobson: Are people using coupons that you clip out of newspapers or are we talking about Groupon and LivingSocial, these online coupon sites?

Lazarus: We're talking the vast majority are still newspaper ones. In fact, the online coupons account for maybe about 1 percent of coupon use these days, so still just a smidge. But that's where all the growth is -- online coupons are growing exponentially, which is why companies like Google are piling into that.

Hobson: All right, time to save money, David. Do coupons really work? Are these people who are using coupons in this downturn saving real money?

Lazarus: They really do work. And the so-called extreme couponers out there can really save big bucks, maybe $1,000 a month off of their bills; 50 percent, perhaps. But that's a whole lifestyle -- you've got to be utterly dedicated and obsessive about your coupons, even to the point of stealing newspapers from your neighbor's yard. That's pretty intense. I'd say for most people, you're going to get savings of 10, 20 percent. But remember this: the vast majority of coupons, especially for food, are for processed foods. So if you get big into coupons, you're not going to be eating really healthy.